Neuralnetworks HAL cleanup -- hardware/interfaces

Does three primary cleanups:
1) Removes unused OperandTypes, creates OEM types
2) Creates explicit ErrorStatus; functions return status
3) IDevice::initialize renamed to getCapabilities,
   IDevice::getSupportedSubgraph renamed to getSupportedOperations

Additionally fixes the corresponding VTS tests.

Bug: 63905942
Test: mm, vts
Change-Id: Ib4c61b9b13963ac2367f21dc3c20e5946eb955a9
diff --git a/neuralnetworks/1.0/IDevice.hal b/neuralnetworks/1.0/IDevice.hal
index 9e19097..ec3b27f 100644
--- a/neuralnetworks/1.0/IDevice.hal
+++ b/neuralnetworks/1.0/IDevice.hal
@@ -22,11 +22,13 @@
 import IPreparedModel;
 
 interface IDevice {
-    initialize() generates(Capabilities capabilities);
+    getCapabilities() generates (ErrorStatus status, Capabilities capabilities);
 
-    getSupportedSubgraph(Model model) generates(vec<bool> supported);
+    getSupportedOperations(Model model)
+            generates (ErrorStatus status, vec<bool> supportedOperations);
 
-    prepareModel(Model model, IEvent event) generates(IPreparedModel preparedModel);
+    prepareModel(Model model, IEvent event)
+            generates (ErrorStatus status, IPreparedModel preparedModel);
 
-    getStatus() generates(DeviceStatus status);
+    getStatus() generates (DeviceStatus status);
 };